How to compile and install iperf on a MIPS based router?

I have a DIR-825 router based on Atheros AR7161 (MIPS) running DD-WRT v24-sp2 std. How can I compile and install iperf on it? Can I compile it directly on the target device, or do I have to cross compile it and then transfer the binary to the target device? Is this possible, and where do I begin? What kind of tools do I need? What's involved in doing something like this? *Side note: I have limited knowledge of Linux, so please provide as thorough answer as possible, and not just some external links. If you do post a link, make sure it links to some article or a blog post that thoroughly explains the process.*